MATHEMATICAL ANALYSIS PROBLEMS LIST 12
4.01.10
(1) Find the formula for Cn = Xn
i=1
b − a n f¡
a + ib − a n
¢, and the compute lim
n→∞Cn: (a) f(x) = 1, a = 5, b = 8, (b) f(x) = x, a = 0, b = 1,
(c) f(x) = x, a = 1, b = 5, (d) f(x) = x2, a = 0, b = 5, (e) f(x) = x3, a = 0, b = 1, (f) f(x) = 2x + 5, a = −3, b = 4, (g) f(x) = x2+ 1, a = −1, b = 2, (h) f(x) = x3+ x, a = 0, b = 4, (i) f(x) = ex, a = 0, b = 1.
(2) Compute the following denite integrals by constructing a sequence of partitions of the interval, corresponding Riemann sums, and their limits:
(a) Z 4
2
x10dx, (xi = 2 · 2i/n), (b) Z e
1
log(x)
x dx, (xi = ei/n), (c)
Z 20
0
x dx, (d)
Z 10
1
e2xdx, (e)
Z 1
0
√3
x dx, (xi = ni33), (f) Z 1
−1
|x| dx, (g)
Z 2
1
dx
x dx, (xi = 2i/n), (h) Z 4
0
√x dx, (xi = 4in22).
(3) Compute the denite integrals:
(a) Z π
−π
sin(x2007) dx, (b) Z 2
0
arctan([x]) dx, (c)
Z 2
0
[cos(x2)] dx, (d) Z 1
0
√1 + x dx,
(e)
Z −1
−2
1
(11 + 5x)3dx, (f) Z 2
−13
1 p5
(3 − x)4 dx, (g)
Z 1
0
x
(x2+ 1)2 dx, (h) Z 3
0 sgn (x3− x) dx, (i)
Z 1
0
x e−xdx, (j)
Z π/2
0
x cos(x) dx, (k)
Z e−1
0
log(x + 1) dx, (l) Z π
0
x3 sin(x) dx, (m)
Z 9
4
√x
√x − 1dx, (n)
Z e3
1
1 xp
1 + log(x)dx, (o)
Z 2
1
1
x + x3 dx, (p)
Z 2
0
√ 1
x + 1 +p
(x + 1)3 dx, (q)
Z 5
0
|x2− 5x + 6| dx, (r) Z 1
0
ex
ex− e−xdx,
1
(s) Z 2
1
x log2(x) dx, (t)
Z √7
0
x3
√3
1 + x2 dx, (u)
Z 6π
0
| sin(x)| dx, (w)
Z π/2
0
cos(x) sin11(x) dx, (x)
Z log 5
0
ex√ ex− 1
ex+ 5 dx, (y) Z π
−π
x2007cos(x) dx, (z)
Z 2π
0
(x − π)2007cos(x) dx. (4) Prove the following estimates:
(a)
Z π/2
0
sin(x)
x dx < 2, (b) 1
5 <
Z 2
1
1
x2+ 1dx < 1 2, (c) 1
11 <
Z 10
9
1
x + sin(x)dx < 1
8, (d) Z 2
−1
|x|
x2+ 1dx < 3 2, (e)
Z 1
0
x(1 − x99+x) dx < 1
2, (f) 2√
2 <
Z 4
2
x1/xdx, (g) 5 <
Z 3
1
xxdx < 31, (h) Z 2
1
1
xdx < 3 4. (5) Compute the following limits:
(a) limn→∞¡1
n+ n+11 +n+21 +n+31 + · · · + 2n1 ¢ , (b) lim
n→∞
¡120+220+320+···+n20 n21
¢, (c) lim
n→∞
¡ 1
n2 +(n+1)1 2 +(n+1)1 2 + (n+3)1 2 + · · · +(2n)1 2
¢· n, (d) limn→∞¡ 1
√n√
2n +√n√12n+1 + √n√12n+2 + √n√12n+3 + · · · + √n1√3n¢ , (e) limn→∞¡
sin(n1) + sin(2n) + sin(3n) + · · · + sin(nn)¢
· 1n, (f) lim
n→∞
¡√4n +√
4n + 1 +√
4n + 2 + · · · +√ 5n¢
· n√1n, (g) lim
n→∞
¡ 1
√3
n+ √3 1
n+1 + √3 1
n+2+ · · · + √31
8n
¢· √31
n2, (h) lim
n→∞
¡√6
n·(√3 n+√3
n+1+√3
n+2+···+√3
√ 2n) n+√
n+1+√
n+2+···+√ 2n
¢, (i) limn→∞¡n
n2 +n2n+1 + n2n+4 +n2n+9 +n2+16n + · · · + n2+nn 2
¢, (j) lim
n→∞
¡4
5n+ 5n+34 +5n+64 + 5n+94 + · · · + 26n4 ¢ , (k) lim
n→∞
¡ 1
7n + 7n+21 +7n+41 + 7n+61 + · · · + 9n1 ¢ , (l) limn→∞¡ 1
7n2 + 7n21+1 +7n21+2 +7n21+3 + · · · + 8n12
¢,
(m) lim
n→∞
1 n
¡e√1
n + e√2
n + e√3
n + · · · + e√n
n¢ , (n) limn→∞¡ 1
√n+√n+31 +√n+61 +√n+91 + · · · + √17n¢ 1
√n, (o) limn→∞¡n2+0
(3n)3 +(3n+1)n2+13 +(3n+2)n2+23 + (3n+3)n2+33 + · · · + n(4n)2+n3
¢, (p) lim
n→∞
¡ n
2n2 +2(n+1)n 2 +2(n+2)n 2 + 2(n+3)n 2 + · · · + 50nn2
¢, (r) lim
n→∞
¡ n
2n2 + n2+(n+1)n 2 + n2+(n+2)n 2 + n2+(n+3)n 2 + · · · + 50nn2
¢.
2